What's funny to me here is that, as a long time Arch user, I have been considering switching to NixOS. One of the most terrifying thoughts to me is that after using the same Arch install for 2 years I will spend ages trying to recreate it if I ever have to. Oh, that and Nix letting you test packages seems like a cool feature.
I've been on arch around a year now and also considered the jump to NixOS. I was actually dual booting it with arch for awhile and I found pretty quickly that the shit documentation was a huge turn off for me. I ended up nuking the nix partition and reclaiming it for arch.
I've found that the Arch wiki works for most distros if you know how to translate it. There have been multiple times I've searched how to do something or how to fix something in Linux and the only useful result is an arch forum or wiki. All I had to do is translate the steps for debian/ubuntu/opensuse/fedora/rpiOS, etc.
The process was usually "search this error" > "this part" isn't working, search "this part error" > arch forum showing steps to fix. Search "where the fuck is this file in <distro>". Get "it's usually here, here, or over here", then do arch steps.
Then there's opensuse, and there's fucking camelcase capitals in their packages (NetworkManager? Seriously?) so I have to Google "opensuse <command/application> package" like a fucking rube.
That and the need to learn a bespoke, weird programming language that will only ever be useful for this one thing have really turned me off of that distro.
What I did is that I've setup a VM with NixOS in it to play with, learn the language and tweak the configuration file.
The great thing about NixOS is that once I was feeling confident enough to switch I installed NixOS on bare metal, loaded the configuration file I prepared in the VM and I instantly had everything installed and running. (Except for the NVidia drivers, fuck nvidia)
Since then I've stayed in nixos and I'm not looking back.